What, if any, adjuvant therapy would you offer a high risk (based on size, location, mitotic rate) GIST patient who is wild type or PDGFRA D842V mutated?  

Unfortunately, there is no evidence that would support the use of postop adjuvant therapy for WT (regardless of the subtype) or PDGFRA D842V mutant high-risk GIST. The SOC would be close observation and consider mutation-appropriate options with measurable/evaluable disease.